Merge pull request #705 from unknownbrackets/jit-vfpu

Small VFPU prefix fixes
Small optimizations and fixes to vertex decoder
Don't need separate variables for writemask. Some optimizations.
VFPUutil style & simplification
Replace "Core" with "Jit" in ini. Don't show Open dialog by default (use Ctrl+A or Ctrl+O to open it).
Delete "Slightly Faster Interpreter".
Remove faster interpreter from headless.
Log an error when vfpu swizzle is used badly.
Add TEMP0 fpu regs to x86 like in armjit.

But... will probably need more and the ability to swap into memory
if we want to deal with prefixes.
Enable VDot and Vec3 in x86 jit.